Torquay Manor 5 Gauge Frames

[Roy BirchParticipant @roybirch29994]

Hello

This is more aimed at members who may have completed the Manor already, I have a firefly in 5 gauge that is only at the frame stage but the frames are notably thicker than the manor frames, around 4.2mm, the manor I got as a part built loco with 2 or more sets of castings but with 1 set having a slide valve and the other having the piston valve cylinders, the frame was already assembled but it was not square and I do not think with the best will in the world that I can correct this as the ongoing build is throwing up problems here and there. My view is now to remake the frames and get them square as I do not want to build a model that when I get to the end does not work very well or look correct, in order to save time I am considering just getting laser cut frames with all the holes in and stretchers as well as front and rear beams, I have checked with Model Engineers Laser to see if they can make the frames in a thicker material along the lines of 4 mm, if I keep the internal distance between the frames the same as they are on the plan I will then be left with an expansion of the frame of 1 mm per side, can anyone tell me who may have built this model already whether or not I am likely to face any serious problems other than extending some shafts by a couple of millimeters I already have a boiler so I have to keep the internal dimensions the same as it is a tight fit already, the reason for using thicker frames is that the firefly locomotive frame at 4.2 mm looks so much more robust and gives you a sense that the Loco can do some serious work. Thankfully all the parts made so far are salvageable.

Many thanks

Roy

[BazParticipant @baz89810]

What thickness does the drawing show for the frames? Get laser cut frames if you can afford them but get them in the thickness stated on the drawing, just my two cents worth.

[duncan webster 1Participant @duncanwebster1]

If you increase the outside dimension of the frames you will open a can of worms. Unless you’re prepared for a lot of redesign I’d stick to the drawing thickness.  If you really want thicker frames make the frame spacers shorter, but that will still affect quite a few other components.

[Dave WoottonParticipant @davewootton]

Martin Evans specified 3/16″ thick steel for Firefly’s frames, presumably because of the cutouts for leading and trailing wheels. On the Manor he specified the more usual for 5″ gauge 1/8″ steel. One of my friends built Firefly and moaned so much about cutting the thick frame steel with a hacksaw I took them to work and milled the profile for him on a huge Huron mill, pre common availability of laser cutting. reminds me he still owes me a pint!

I have been working on a part built Springbok where no allowance was made with the frame spacers for the difference between 1/8″ and 3mm steel frames, I had to shim all the frame spacers to get the outside dimension correct, a bit tedious but easily do-able. If you increase the thickness of the frame material on the Manor and keep the outside dimension correct, which you will need to do to get the cylinders and motion to line up. It will decrease the width between the frames which could well cause problems with clearance for the outer firebox, easy to change if you are building your own boiler, but an existing boiler built to the drawings might not fit, worth checking. Changing fundamental dimensions often has an unfortunate habit of biting you in the bum later!

[Roy BirchParticipant @roybirch29994]

I understand now, it looks a really sturdy frame, does anyone think my logic about remaking the frames is a good idea or should I persevere with what I have, the axles all line up and are square but the frames are just offset a small amount, my view is if I started with laser cut frames I could get up to where I am now reasonably quickly.

[Nigel Graham 2Participant @nigelgraham2]

Only “reasonably quickly” if the frames are of the thickness specified on the drawings, otherwise you will run into those problems others point out.

Also note that laser-cutting can case-harden the cut edge, potentially making life awkward.

That questioned millimetre extra each side is not what you want, as it risks problems with the axle-boxes and horns, axles and wheels.  Perhaps the cylinders, crossheads, etc. too.

 

I’d be inclined to analyse the faults first and see if they can be corrected sensibly. It may be as relatively simple as making new buffer-beams or modifying stretchers.

For example, if the “offset” is lengthways so the ends of the frames overlap each other slightly, are the overlaps small enough to trim without affecting the fit of anything else, or spoiling the appearance of the finished locomotive?

[Author]

Posts